The Franck Muller Aeternitas Mega 4, the most complicated wristwatch ever produced, is coming to auction at Christie's Important Watches sale in Hong Kong on May 30.
The 2010-made watch has never appeared at auction before, and will arrive with a $600,000-1.2m estimate.
"This majestic timepiece with 1,483 parts combined to create 36 functions is known as the most complicated wristwatch ever produced to date," states Christie's.
"Collectors and scholars will unanimously agree that this truly magnificent work of art takes a prominent position in the history of watchmaking as one of the most exclusive and important wristwatches ever manufactured."
The largest selection of Patek Philippe watches ever assembled at an Asia auction will also feature.
A pink gold wristwatch with centre seconds and cloisonné enamel, Reference 2481 The Lighthouse, will star with a $200,000-300,000 valuation.
It was one of the largest wristwatches ever seen when it first appeared in 1950.
These are exciting time for collectors of Patek Philippe; four world record prices were broken for the manufacturer in New York on April 25, with one piece achieving $902,500.
Eight Harry Winston Opus Series watches will also be up for grabs. It is the largest collection of Winston Opus timepieces ever to arrive at auction.
One of just six Opus 6s ever produced is among the collection. Featuring a rare Double Tourbillon 30°, it is expected to make $320,000-500,000.
More than 500 timepieces will be on offer to collectors in all, with a combined estimate of $16m.
Christie's global watch sales surpassed $100m for the first time last year.
Entry level investors should take a look at this Longines Olympic Series watch, priced at just £950 with Paul Fraser Collectibles.